In some organizations, users purchase servers that are maintained by information technology (IT) departments. The servers may be located in facilities such as data centers. The physical hardware and the security of the servers are maintained by facility managers. Servers may be purchased for specific applications or projects. Over time and as the projects are completed, need for the applications may diminish. As such, racks and data centers may host unused servers. These servers are referred to as zombie servers. The terms “zombie server” and “comatose server” can be used interchangeably. Zombie servers may be regularly maintained by IT specialists even though the zombie servers are no longer used by customers. Besides IT resources, zombie servers occupy rack space, consume energy (e.g., power), and burden cooling resources. Expenses on zombie servers can be considered as wasted resources because the zombie servers do not contribute to productivity. In some environments, zombie servers may occupy 10% to 20% of servers in a data center and/or rack. A similar situation exists even in virtual environments where resources get allocated to an application and remain unused. For example, a virtual server may be created without being used. The virtual server may be considered a virtual zombie server. As used herein, the term “zombie server” also includes virtual zombie servers.
In a number of previous approaches, zombie servers are identified by tracking processor utilization. However, tracking processor utilization to identify zombie servers may include a number of limitations. For example, a processor of a server may process services that are not consumed by customers (e.g., users). For example, management software executed on the server may contribute to processor utilization without a customer utilizing the server. Management software and/or services that may occur in zombie servers that may be carried out without a consumer's request may include backup services, security services, and virtualization services, among others. That is, management services may contribute to processor utilization such that a server receiving the management services may appear to be utilized by a customer when the server is not actually utilized by the customer.
Identifying a zombie server may be difficult because non-zombie servers (e.g., servers that are utilized by customers) that are used for productivity applications may also have low utilization. That is, there may be little difference in processor utilization as it corresponds to zombie servers and non-zombie servers.